Refactor employees view to use master3

tailbone/forms2/core.py

@@ -75,6 +75,38 @@ class CustomSchemaNode(SQLAlchemySchemaNode):
         """
         return get_association_proxy(self.inspector, field)
 
+    def association_proxy_target(self, field):
+        """
+        Returns the property on the main class, which represents the "target"
+        for the given association proxy field name.  Typically this will refer
+        to the "extension" model class.
+        """
+        proxy = self.association_proxy(field)
+        if proxy:
+            proxy_target = self.inspector.get_property(proxy.target_collection)
+            if isinstance(proxy_target, orm.RelationshipProperty) and not proxy_target.uselist:
+                return proxy_target
+
+    def association_proxy_column(self, field):
+        """
+        Returns the property on the proxy target class, for the column which is
+        reflected by the proxy.
+        """
+        proxy_target = self.association_proxy_target(field)
+        if proxy_target:
+            prop = proxy_target.mapper.get_property(field)
+            if isinstance(prop, orm.ColumnProperty) and isinstance(prop.columns[0], sa.Column):
+                return prop
+
+    def supported_association_proxy(self, field):
+        """
+        Returns boolean indicating whether the association proxy corresponding
+        to the given field name, is "supported" with typical logic.
+        """
+        if not self.association_proxy_column(field):
+            return False
+        return True
+
     def add_nodes(self, includes, excludes, overrides):
         """
         Add all automatic nodes to the schema.
@@ -117,13 +149,9 @@ class CustomSchemaNode(SQLAlchemySchemaNode):
             else:
 
                 # magic for association proxy fields
-                proxy = self.association_proxy(name)
-                if proxy:
-                    proxy_prop = self.inspector.get_property(proxy.target_collection)
-                    if isinstance(proxy_prop, orm.RelationshipProperty):
-                        prop = proxy_prop.mapper.get_property(name)
-                        if isinstance(prop, orm.ColumnProperty) and isinstance(prop.columns[0], sa.Column):
-                            node = self.get_schema_from_column(prop, name_overrides_copy)
+                column = self.association_proxy_column(name)
+                if column:
+                    node = self.get_schema_from_column(column, name_overrides_copy)
 
                 else:
                     log.debug(
@@ -167,7 +195,8 @@ class CustomSchemaNode(SQLAlchemySchemaNode):
 
             name = node.name
             if name not in dict_:
-                if not self.association_proxy(name):
+                # we're only processing association proxy fields here
+                if not self.supported_association_proxy(name):
                     continue
 
                 value = getattr(obj, name)
@@ -229,7 +258,7 @@ class CustomSchemaNode(SQLAlchemySchemaNode):
             else:
 
                 # try to process association proxy field
-                if self.association_proxy(attr):
+                if self.supported_association_proxy(attr):
                     value = dict_[attr]
                     if value is colander.null:
                         # `colander.null` is never an appropriate
@@ -306,6 +335,10 @@ class Form(object):
         if key in self.fields:
             self.fields.remove(key)
 
+    def remove_fields(self, *args):
+        for arg in args:
+            self.remove_field(arg)
+
     def make_schema(self):
         if not self.model_class:
             # TODO
@@ -566,10 +599,11 @@ class Form(object):
         return HTML.tag('pre', value)
 
     def obtain_value(self, record, field_name):
-        try:
-            return record[field_name]
-        except TypeError:
-            return getattr(record, field_name)
+        if record:
+            try:
+                return record[field_name]
+            except TypeError:
+                return getattr(record, field_name)
 
     def validate(self, *args, **kwargs):
         form = self.make_deform_form()